Akash Kagi

Hello, Though the questions that I post in this Homework help section are actually not related to my homework but appear in my 9th STD physics text book with the label "Think It Over", I feel it is appropriate to post them here, because even after much thinking I have not been able to find right explanation. The question is- "The aluminium wires used in the transmission of electric current are not insulated. Why?" Thanks.

Hello, Though the questions that I post in this Homework help section are actually not related to my homework but appear in my 9th STD physics text book with the label "Think It Over", I feel it is appropriate to post them here, because even after much thinking I have not been able to find right explanation. The question- "Is work done when rolling a marble on a frictionless plate?" Thanks.

Which extra conditions?

Thanks Swansont, For your kind attention. Basically, I have not understood the question itself. The question comes under the section ACCELERATION DUE TO GRAVITY It reads as under- Objects thrown vertically upwards move for a certain distance and then fall back to the ground. It is due to the gravitational force of the earth. Every particle of matter in the universe attracts every other particle. The credit proving this, stating the universal law of gravitation and inventing the method of calculating gravitational force goes to Sir Isaac Newton. A body accelerates if and only if the resultant of all the forces acting on it is not equal to zero. Does a body falling towards the ground accelerate due to gravitational force? And then in a box with the heading THINK IT OVER the question is given.

Hello everybody, Today is my first day on science forum. I am studying in 9th std. I came upon the following question in my text book, which I was unable to answer. So I am posting this on the scince forum, seeking your help. The question is- "During which situation may an object dropped from a certain height not fall to the earth?" Thanks and regards.